Organotin compounds are metal organic compounds formed by the direct combination of tin and carbon. They are widely used in the fields including agriculture, catalytic chemistry, pharmaceutical chemistry, stabilizing agent, antifouling coating, material anticorrosive and textile, and are also important organic synthetic intermediates. It is an important application of organotin compounds to act as a catalyst in the organic reaction, as it has the characteristics of high yield, high selectivity and non-corrosive to reactors. However, there are two major shortcomings when it is applied to the curing of thermosetting resins, one of which is the high activity under low concentration, this feature usually makes the catalytic curing of thermosetting resin runs so fast that is difficult to be controlled, so that the cross-linked structure of the cured product is inhomogeneous, and it is difficult to obtain a cured product with good comprehensive properties as expected. Therefore, the organotin used for the curing of the thermosetting resin should have appropriate reactivity, not high activity. Secondly, the homogeneous dispersion in the resin is a prerequisite for obtaining a cured product having excellent comprehensive properties, whereas the conventional organotin catalyst does not have an active group capable of interacting with the resin.
It is worth mentioning that the toxicity of organotin compounds has been fully confirmed, this shortcoming restricts the wide applications of organotin compounds. The research of low toxic organotin-based initiator has become a common concern. Previous researches showed that the introduction of silicon atom could reduce the toxicity of organotin compounds (literature: Patai S, Rappoport Z. Bioorganosilicon Chemistry [M]. John Wiley and Sons: 1989, 1143-1168.). However, the content of silicon in available silicon-containing organotin is very low and the tin loading is still high.
In summary, there is important application value to develop a new low-toxic organotin that can be used for the curing reaction of thermosetting resins.